Updated: 2021/Apr/14


BN_mod_inverse(3)                   OpenSSL                  BN_mod_inverse(3)



NAME
       BN_mod_inverse - compute inverse modulo n

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/bn.h>

        BIGNUM *BN_mod_inverse(BIGNUM *r, BIGNUM *a, const BIGNUM *n,
                               BN_CTX *ctx);

DESCRIPTION
       BN_mod_inverse() computes the inverse of a modulo n places the result
       in r ("(a*r)%n==1"). If r is NULL, a new BIGNUM is created.

       ctx is a previously allocated BN_CTX used for temporary variables. r
       may be the same BIGNUM as a or n.

RETURN VALUES
       BN_mod_inverse() returns the BIGNUM containing the inverse, and NULL on
       error. The error codes can be obtained by ERR_get_error(3).

SEE ALSO
       ERR_get_error(3), BN_add(3)

COPYRIGHT
       Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.



1.1.1i                            2018-09-23                 BN_mod_inverse(3)